Method of twining threads



Jan. 12, 1965 E. HAMEL METHOD OF TWINING THREADS Filed July 20, 1962 \'umann`nnwwW//W///////l/// 10' FIGB INVENTOR AGENT i two stages.

United States Patent j O 3,164,950 METHOD F TWINING THREADS Edmund Hamel, Romanshorn, Thurgau, Switzerland, as-

signor to Hamel Projektierungsund Verwaltungs A.G., Thurgau, Switzerland, a corporation of Switzerland Filed July 20, 1962, Ser. No. 211,301 Claims priority, application Germany,V July 27, 1961, H 43,261 Claims. (Cl. 57-156) My present invention relates to the ltwining of threads from vegetable, animal or synthetic fibers by the blending or gathering of these threads or filaments into a yarn and the twisting'of the latter to secure the threads agamst relative longitudinal displacement.

In my U.S. Patent No. 2,972,856, issued February 28, 1961, I describe and claim a process for producmga twisted yarn from two or more filaments or threads m In the course of the initial stage the filaments are blended by being brought together at relatively high speed and given a slight protective twist at a relatively low number of turns per unit length. In the finishing stage the yarn is again twisted, this time at a relatively high number of turns per unit length in the d1rection of the initial twistingf The patent also describes and illustrates apparatusfor carrying out the aforementioned two-stage process. Y h

TheV patented process is an improvement over earlier methods of twining threads wherein two or more filaments were displaced generally parallel to each other and twisted in a single step to produce the finished threads. The latter process, while avoiding relative longitudin-al displacement of the threads after such twisting, was unable to prevent such relative displacement as the threads were blended together and thus resulted in yarn of questionable value. In both of these processes the threads lwere twisted together oppositely to the direction of twist of the threads themselves; vThus, in the two-stage process, the threads fed at a relatively high speed were `twisted together counter to the twists Vof the respective filamentsl for the relatively low number of turns per unit length and thereafter twisted in the same direction, also oppositely to the thread twist for a relatively high number of turns per unit length. The latter technique has the important disadvantage that, when` the threads are intertwined with a relatively small number of turns per unit length in a directionfopposite to the thread twist, the tensile strength of the individual threads is materially reduced and the threads tend to shift relatively. Consequently, the weakened threads have been found to rupture in the course of the subsequent finish-twisting stage. As a result of the high degree of breakage-of the threads a considerable slowdown occurs in the two-stagev process. Y

It is an object of the present invention to provide a method of twining threads adapted to obviate4 the foregoing disadvantages.

A Inore specific object of the invention is to'provide a method of twining threads adapted to reduce the tendency toward thread breakage while yielding a high-V quality twisted yarn.

These objects have been realized, in accordance with the invention, by the provision of a method of making yarn whereby a plurality of threads, each one adv-antageously having a twist in one direction, are gathered into a yarn to which is imparted a preliminary twist with a relatively low number of turns in the direction of twist of the individual threads. Thus, there is no tendency to loosen the threads themselves and reduce their tensile strength in the course of the first stage. Subsequently, the yarn is twisted with a relatively high number of turns in the opposite direction to yield a tightly twisted product ber of turns).

3,l64,950 Patented Jan. l2, 1965 wherein the threads are intertwined with a twist in the direction opposite that `of the individual thread twists.

. According to a further feature of the present invention the preliminary twist is carried out at a relatively high rate of travel of the yarnas described in my abovementioned patent. Thus, the forward speed of the thread during the first stage may be on the order of several hundred meters per minute while the minimum ratio of the high and low numbers of`turns per unit length is on the order of 10 to l. In this connection it may be noted that the preliminary twist may range between approximately 1 and 80 turns per meter whereas the finished twist is on the order of 1000 turns per meter. In contradistinction to my above-mentioned patent, however, the preliminary twist of the present invention is carried Vout in the direction of the thread twist while the finishing twist is carried out in the opposite direction.

Among the advantages of the present method is the substantial reduction of the possibility of thread breaking andthe substantial increase in the speed of yarn production in view of the greatly reduced number of breakdowns resulting from such thread breakage. While this method at first glance may appear to involve a reduction in production efficiency, since the initial twist is unwound in the course of the finishing twist, ithas been found that the finishing twist of the patent process was generally carried out with fewer numbers of turns per minute in spite of greater machine capacity in order to reduce the amount of thread breakage. It is thus only necessary to speed up the finish-twining machine slightly to overcome the apparent loss in eiiiciency. The corresponding decrease inthe down time of the apparatus affords the possibilities of a larger rate of production of the yarn with existing types of machines. The above and other objects, features and advantages ofthe present invention will become more readily apparent fromthe following detailed description, reference being made tothe accompanying drawing in which:

FIG. 1 diagrammatically illustrates the first stage of a two-'stage twining process according tothe present in- Ventron;

FIG. 2 is a diagrammatic cross-sectional view illustrating the second stage of the process; and FIG. 3 is an enlarged plan view of the yarn produced 1n accordance with the present method.

Prior to entering into discussion of the apparatus shown in FIGS. l and 2 reference is made to FIG. 3 from whence it may be seen that a pair of individual threads 1' and 2', each having -a characteristic twist in one direction, are blended together in the course of a firststage I by imparting to them a preliminary twist ybetween 1 and 80 turns per meter in the same direction. Subsequently, in stage II the two threads are twisted in the opposite direction with a relatively highfnumber of turns per unit length (eg. at least about ten times the preliminary numv It has been found surprisingly that the finishing twist, while unwinding the preliminary twist, does not cause relaxation or unraveling of the individual threads to an extent that they could be readily rupturable in the course of the finish-twining.

-In FIG. 1 I show-the blending or lirninary twisting steps of the present invention. The threads or laments 1' and 2', individually dispensed by a pair of spools 1 and 2, are led together over a deflecting roller 5 and through an eye 6 to a suitable transport mechanism such as a pair of parallel rollers 7, 8 of different diameters. The gathered filaments pass one or more times around the two rollers, which are driven by means not shown, in the direction illustrated by the arrows. After passing through another stationary eye 9 the resulting yarn 1t) is given a slight initial or preliminary twist, equivalent to that shown at stage I in FIG. 3,

gathering and preby being wound on a bobbin -15 at a controlled rate following the traverse of a traveler 14 which is freely displaceable on the non-rotating spinning ring 11 surrounding bobbin 15. This bobbin is removably seated on a vertical spindle 22 which is journaled in a stationary bracket 24 and is rotated by a bell `13 at a predetermined speed with respect to the feed rollers- 7 and 8. Spinning ring 11 is mounted on a frame 12 adapted to move vertically in a manner known per se and shown in my above-mentioned patent.

If the peripheral speed of bobbin 15 exceeds the linear speed of yarn as imparted to it by the transport mechanism 7, S, the traveler 14 will revolve about the bobbin axis at a rate commensurate with the difference of these two speeds. Since the effective forward speed of the yarn and, therefore, the rate of twist per unit length .will also be affected by the reciprocating machine of the frame 12, this latter machine should be slow in comparison with the peripheral velocity of roller 8 so that the rate of twist will be substantially the same during the upstroke and the downstroke of ring 11.

Generally, as pointed out in my Patent No. 2,972,856, the preliminary twist can range between l and 80 turns per meter and advantageously is 25 to 30 turns per meter' at a linear speed of approximately 400 meters per minute. The linear speed may, however, be on the order of 50 to 600 meters per minute.

In FIG. 2 I show the second stage II of the present method. The loaded bobbin 15, taken from the spindle 22 of FIG. 1, is now seated within a generally cylindrical shell 16 on a stud 16 which is rigid with the shell and has an outward extension journaled in a bracket 25 whereby the members 15 and 16 are rotatable as a unit about a vertical axis. Motion is imparted to this unit by a belt drive 23. The top of shell 16 is closed by a removable lid 16" through which the finished thread 10 passes outwardly by way of an eye 19 to a take-up reel 20. The lead 16" carries a hook 1S which -frictionally engages the thread 10' so as to twist it at the rate of rotation of unit 15, 16 without materially impeding its ad- Vance. This advance is controlled by a driven friction roller 21 whose supporting arm 26 is urged by a spring 27 in contact with the periphery of the reel 20. The drive means for this roller is fully shown in my previously mentioned patent.

While the take-up speed of the reel may vary within wide limits in accordance with requirements, its correlation with the rotary speed of bobbin 15 and shaft 16 should be such that the additional twist now imparted to the yarn should be considerably greater than that previously given to it; whereas both twists in the patented process are in the same direction, the unit 15, 16 in the present case is rotated in the direction of arrow A so that the finishing twist is opposite the preliminary twist. Since the finishing twist may be on the order of 1000 turns per meter and may range up to 5000 turns per meter, it should be noted that the bobbin 15, whose rotary speed may again be on the order of 10,000 to 12,000 revolutions per minute will be required to be slightly faster since the number of twists actually effected must be equal to N -i-M where N is the number of preliminary turns per meter and M is the number of turns per meter in the finished yarn.

The invention as described and illustrated is believed to admit of any modifications and variations which will fi be readily apparent to persons skilled in the art and are intended to be included within the spirit and scope of the invention as claimed.

I claim:

l. A method of twining a plurality of fibrous threads twisted in a first direction, comprising the steps of gathering said threads into a yarn, imparting to said yarn a preliminary twist with a relatively low number of turns per unit of yarn length in said first direction to limit relative longitudinal movement of said threads, and subsequently imparting to said yarn a finishing twist with a relatively high number of turns per unit of yarn length in a direction opposite said first direction.

2. A method of twining a plurality of fibrous threads, comprising the steps of gathering said threads into a yarn, imparting to said yarn a preliminary twist with a relatively low number of turns per unit of yarn length in a first direction to limit relative longitudinal moverrient of said threads, and subsequently imparting to said yarn a finishing twist with a relatively high number of turns per unit of yarn length in a direction opposite said first direction, the minimum ratio of said high and low numbers of turns being about ten to one.

3. A method of twining a plurality of fibrous threads A twisted in a first direction, comprising the steps of gathering said threads into a yarn, imparting to said yarn a preliminary twist with a relatively low number of turns per unit of yarn length in said first direction to limit relative longitudinal movement of said threads, and subsequently imparting to said yarn a finishing twist with a relatively high number of turns per unit of yarn length in a direction opposite said first direction, the minimum ratio of said high and low number of turns being about ten to one.

4. A method of twining a plurality of fibrous threads twisted in a first direction, comprising the steps of gathering said threads into a yarn, advancing said threads at a relatively high speed while imparting to said yarn a preliminary twist with a relatively low number of turns per unit of yarn length in said first direction to limit relative longitudinal movement of said threads, and subsequently advancing said threads at a relatively low speed while imparting to said yarn a finishing twist with a relatively high number of turns per unit of yarn length ori the order of 1000 turns per meter in a direction opposite said first direction, the minimum ratio of said high and low number of turns being about ten to one.

5. A method of twining a plurality of fibrous threads twisted in a first direction, comprising the steps of gathering said threadsinto a yarn, advancing said threads at a relatively high speed on the order of several hundred meters per minute while imparting to said yarn a preliminary twist with a relatively low number of turns per unit of yarn length in said direction to limit relatively longitudinal movement of said threads, and subsequently advancing said threads at a relatively low speed while imparting to said yarn a finishing twist with a relatively high number of turns per unit of yarn length on the order of 1000 turns per meter in a direction opposite said first direction.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A METHOD OF TWINING A PLURALITY OF FIBROUS THREADS TWISTED IN A FIRST DIRECTION, COMPRISING THE STEPS OF GATHERING SAID THREADS INTO A YARN, IMPARTING TO SAID YARN A PRELIMINARY TWIST WITH A RELATIVELY LOW NUMBER OF TURNS PER UNIT OF YARN LENGTH IN SAID FIRST DIRECTION TO LIMIT RELATIVE LONGITUDINAL MOVEMENT OF SAID THREADS, AND SUBSEQUENTLY IMPARTING TO SAID YARN A FINISHING TWIST WITH A RELATIVELY HIGH NUMBER OF TURNS PER UNIT OF YARN LENGTH IN A DIRECTION OPPOSITE SAID FIRST DIRECTION. 